Pain measurements in right-left cerebral lesions

Left- and right-brain damaged (BD) subjects were examined to ascertain whether psychophysical parameters of pain-pain threshold (P), tolerance threshold (T), and pain endurance (E)-were modified by brain damage and whether differences exist between LBD and RBD. Noxious stimulus was provided by electrical stimulation. Results showed that P and T scores for the paralysed arms were consistently higher than those of the contralateral side. This was not simply due to modified sensitivity alone; in the RBD group hemi-inattention and aphasia in the LBD group also played a role. A significantly hightened value of pain endurance was found only in the healthy arm in the RBD group.